- Johannes Kepler (December 27 1571 – November 15 1630) was a German Lutheran mathematician, astronomer and astrologer, and a key figure in the 17th century astronomical revolution. He is best known for his laws of planetary motion, which provided one of the foundations of Isaac Newton’s law of universal gravitation.
- Homemade liquid nitrogen generator using Joule Thomson Throttling (homemadeliquidnitrogen.com)
I determined that there was no good tutorial on how the average person can liquefy nitrogen or air. A few references to cryocoolers, which use an internal helium Stirling engine to create a cold head exist, and I even saw one person use this as a means to liquefy nitrogen, allowing the gas to condenses as it passes over the head. This method is cheating because it relies on a self-contained refrigeration unit. I wanted to do this using regenerative cooling just like Carl Linde back in 1895.